Test custom order in CSScomb: http://pastebin.com/s5WQjmBg

Input

.nani {
  left: 0;
  // csscomb: false
  top: 0;
  color: tomato;
  //csscomb: true
  z-index: 0;
  position: fixed;
}

Output

.nani {
  position: fixed;
  left: 0;

  z-index: 0;
  // csscomb: false
  top: 0;
  color: tomato;
  //csscomb: true
}